The IEEE 802.21 standard relates to mechanisms and procedures that aid in the execution and management of inter-system handovers. Under the IEEE 802.21 standard, three main services can be accessed by mobility management (MM) applications in order to aid in the management of handover operations and system discovery and system selection. These three services include an event service, an information service and a command service, which are delivered to prospective users using a common uniform interface, regardless of the underlying access technologies supporting the communication towards the core network.
A method which supports the delivery of event services is needed to determine when an event is to be triggered based on the prevailing characteristics of the underlying technology. The underlying technology could be supported by the 3GPP specification, 3GPP2 and wireless local area networks (WLANs), (e.g., IEEE 802.11 or IEEE 802.16), and the like.
Currently, there are no procedures or functionality to generate triggers toward upper layers, based on information provided by the 3GPP underlying layers. The IEEE 802.21 specification outlines triggers that should be sent to upper layers. However, the IEEE 802.21 specification does not describe how events are triggered when the underlying physical resources are based on 3GPP technology. Therefore a method capable generating these triggers is required.